Mysteries! There is no such thing as a mystery in connection with any crime, provided intelligence is brought to bear upon its investigation. So says a rather down-at-heel elderly gentleman to young Polly Burton of the Evening Observer, in the corner of the ABC teashop on Norfolk Street one afternoon. Once she has forgiven him for distracting her from her newspaper and luncheon, Miss Burton discovers that her interlocutor is as brilliantly gifted as he is eccentric - able to solve mysteries that have made headlines and baffled the finest minds of the police without once leaving his seat in the teahouse.